麻豆传媒

In a randomized trial, surgery to widen and stabilize the soft palate and reduce tongue size improved outcomes among patients with moderate-to-severe obstructive sleep apnea (OSA) for whom conventional treatments had failed.

In early findings from the multicenter trial, palatal surgery combined with minimally invasive tongue volume reduction reduced the number of sleep apnea events and improved patient-reported sleepiness at 6 months, compared with ongoing medical management, according to Stuart MacKay, MD, of the Illawarra ENT Head and Neck Clinic in Wollongong, Australia, and colleagues.

As shown in the team's study online in , other polysomnography measures of sleep apnea severity, including arterial oxygen saturation and cortical arousal frequency, as well as partner-reported snoring and patient-reported quality of life were also improved in the surgery patients at 6 months, but 57% of patients still had moderate to severe residual sleep apnea on polysomnography at 6 months, and oxygen saturation continued to fall below 85% in some patients.

The study is among the first to explore a combined palatal and tongue reduction surgical approach, and the investigators noted that additional research will be needed to understand the clinical utility, long-term efficacy, and safety of the surgical strategy for treating OSA.

"Most patients with OSA have multilevel obstruction, including tongue size due to fat deposition. Thus, this trial of multilevel surgery supports a broader role for upper airway surgery to manage OSA and expands on an earlier randomized clinical trial of multilevel minimally invasive surgery in patients with mild disease," the researchers wrote.

In addition, they said, this multilevel approach showed a greater treatment effect than has been shown in trials of uvulopalatopharyngoplasty alone, with a similar adverse event risk.

Writing in an , Sean M. Caples, DO, and colleagues from the Mayo Clinic in Rochester, Minnesota, said the study "should be considered a platform for the new era in clinical trials of upper airway surgery for OSA."

In an interview, Caples praised the rigorous design of the study, which was conducted at six surgical sites across Australia, but called the findings "somewhat disappointing."

"After surgery there was still a large group of patients with residual sleep apnea, so I suspect that this approach is probably not going to be the game changer everyone is looking for in the treatment of sleep apnea," he told 麻豆传媒.

In addition, while continuous positive airway pressure is highly effective for improving OSA symptoms, a large number of patients either won't use or cannot tolerate it, he added.

Study Details

The SAMS trial included 102 adults with symptomatic moderate or severe OSA for whom conventional treatments had failed. Patients were enrolled from August 2014 to November 2017, with follow-up until August 2018.

Study participants were randomized to have either multilevel surgery (51 patients) or ongoing medical management (also 51), which included advice on OSA-related lifestyle and health interventions such as sleep positioning, weight loss, and management of nasal obstruction.

Surgery consisted of modified uvulopalatopharyngoplasty to widen and stabilize the velopharynx and seven to nine submucosal insertions of a radiofrequency-in-saline wand to reduce tongue volume. The seven surgeons recruited to perform the multilevel procedure attended a training workshop designed to standardize the surgical technique.

The primary study outcomes were the apnea-hypopnea index (AHI: the number of apnea and hypopnea events per hour, with more than 30 indicating severe OSA) and the Epworth Sleepiness Scale (ESS: range of 0 to 24, with more than 10 indicating pathological sleepiness). The researchers assessed baseline-adjusted differences between the two treatment groups at 6 months.

Mean participant age was 44.6 (SD 12.8); 18% were women, and 89% completed the trial.

The mean AHI was 47.9 at baseline and 20.8 at 6 months among the surgery group and 45.3 at baseline and 34.5 at 6 months among the medical management group (mean baseline-adjusted between-group difference at 6 months, −17.6 events/hr, 95% CI −26.8 to −8.4, P<0.001).

The mean ESS was 12.4 at baseline and 5.3 at 6 months in the surgery group and 11.1 at baseline and 10.5 at 6 months in the medical management group (mean baseline-adjusted between-group difference at 6 months −6.7, 95% CI −8.2 to −5.2, P<0.001).

Two participants (4%) in the surgery group had serious adverse events, including one patient who had a myocardial infarction on postoperative day 5 and one who was hospitalized for observation following hematemesis of old blood.

In their editorial, Caples and colleagues said the study represents "a solid foundation for future investigations, although several issues deserve consideration."

"First, surgery was effective at preventing upper airway collapse in some patients but not in others, suggesting that selection criteria will need to be refined in future trials," the editorialists continued. "Second, as in other treatment trials of OSA, women and minority populations were underrepresented, highlighting the importance of including patients from these groups in future trials. Third, because the follow-up time was only 6 months, longer-term data from this trial and future trials will be needed to test the durability of treatment effect over time. It is conceivable that with aging or weight gain, the surgical effect on soft tissue recedes."

Caples and co-authors concluded that comparative efficacy trials are needed to compare outcomes from the multilevel surgical strategy with other surgical procedures, including maxillomandibular advancement and upper airway stimulation.

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